Sequential serum samples from patients with urogenital malignancies (prostate, bladder, kidney) are analyzed immunoelectrophoretically vs. tumor extracts from the autochthonous host in order to determine those stages in tumor progression or regression at which tumor-directed antibody is detectable. Serum is tested under both non-dissociating conditions and conditions known to dissociate specific immune complexes. Relative immunoreactivity under normal and dissociating conditions provides a baseline to correlate clinical parameters in order to determine a prognostic index and to assess the impact of therapeutic modality. Those patient sera that show a high specific immune complex titer are chromatographically fractionated to enrich for the reactive antibody component of immune complexes. Patient sera which exhibit a high titer vs. autochthonous tumor extract are further analyzed by two-dimensional SDS-polyacrylamide gel-immunoelectrophoresis; such two-dimensional analyses should provide a consistent molecular weight profile for those antigens in prostate, bladder, and kidney carcinomas that are recognized by humoral antibodies in patient sera.